The park is home to the United States's only still-operating Dutch windmill.

Former self-sufficient mental institution now a planned community.

Largest tulip festival in America, includes fireworks, a parade, and a carnival.

A crumbling mountain resort that looks like it was abandoned in an instant.

This enchanting forest trail leads to ethereal abodes and a giant bird's nest.

Though its branches are painted bright colors by generations of locals, the tree is said to be a haunted portal to hell.

This shallow cave got its name from copious amount of human bones found inside.

A popular place to pick up prehistoric coral fossils from the time when Michigan was an ocean.

A subterranean world of tunnels links several buildings of this rare 19th-century asylum.

Island where motor vehicles are banned -- home to the only carless highway in the United States.

Strange physical sensations and optical contradictions keep visitors coming back for more.

This national park on the shore of Lake Michigan features remarkable dunes that lie at the heart of a Chippewa legend.

Hell on Earth is actually a small town in Michigan where anyone can be mayor for a day.

The highway's southernmost spot is a beloved local attraction.

The only castle in North America to ever house European sovereigns.

A church dedicated to the Mexican skeleton saint.

Every equinox this Maya pyramid puts on a spooky ancient light show.

Frida Kahlo's childhood home, now a museum of her life and works.

An island filled with hundreds of hanging, decomposing, decapitated dolls.

This island hill is strewn with boulders carved by shipwreck victims from the age of sail.

A 220-foot deep watery drop-off, filled with marine life.

Uninhabited islet in the Caribbean is the sanctuary of giant lizards.

You may get stranded and everyone's peeing in the water, but at least there's cocktails!

Cavernous opening completely encased in Karst limestone.